Radio control apparatus



Oct. 21, 1947. w. L. DUNN RADIO CONTROL APPARATUS Filed Feb. 26. 1940 uww Patented Oct. 21, 1947 RADIO CONTROL APPARATUS William L. Dunn,Chicago, Ill., assignor, by mesne assignments, to Belmont RadioCorporation, Chicago, 11]., a corporation of Illinois ApplicationFebruary 26, 1940, Serial No. 320,833

11 Claims.

My invention relates in general to control apparatus and more inparticular to a manually operated tuning device for a radio receiver,sometimes called a manually operated automatic tuner.

An object of my invention is to provide an improved radio tuning device.

A further object of my invention is to provide a simplified manuallyoperated radio tuner which is actuated by a push-button operating in alinear stroke.

Another object of my invention is to provide a radio tuner with acushioned actuating structure having a pleasant feel during manualoperation, and acting when in latched position to absorb shocks, jars,and other undesired movements in the tuner and thereby prevent injurythereto.

A still further object of my invention is to provide a tuning device foraradio receiver including resonant frequency changing apparatus andcontrol apparatus therefor with a sturdy link connection therebetween.

One of the features of my invention which includes, in one embodiment, arotary control assembly and an actuating unit therefor, is the provisionof a manually operated actuating unit having a yielding portion thereinto provide a more pleasant "feeling" structure when operating the same,and permit play in the complete structure intermediate the rotarycontrol assembly and actuating unit when in operated position withoutultimately disturbing the tuned position of the control assembly.

Other objects and features of my invention will be apparent from thefollowing description taken with the drawings in which:

Fig. 1 is a side elevation of the complete tuning device with a portionof the frame therefor broken away.

Fig. 2 is a plan and sectional view of the structure of Fig. 1 on asmaller scale, taken along the line 2-2 thereof.

Fig, 3 is a fragmentary detail view showing the V actuating unit in anintermediate operating position.

In practicing my invention I provide a manually operated automatictuning device which includes resonant frequency ,changing means for a,radio receiver, and means for moving such resonant frequency changingmeans to predetermined tuning positions. The latter means includes arotary shaft, a plurality of control members mounted on the shaft andnormally retained against rotation thereon, and actuating unitscorresponding to the control members. Each actuating unit includes apivoted lever for directly engaging and moving a corresponding controlmemher, and a substantially linearly movable actuator 5 having apush-button on one end for finger engagement to operate the actuatingunit and hence the control device, and being operatively connected atits other end with the pivoted lever. The connection between theactuator and lever includes a guide pin on the lever riding in acorresponding slot in the actuator adjacent the end thereof, and aspring supported on the actuator at a fixed retaining portion at one endof the spring, and with the other end of the spring bearing directly orindirectly against the lever. In idle position the spring normallymaintains the actuae tor and lever at extreme positions as limited bythe guide pin in the slot. On at least one portion of the operatingstroke for the actuator, the

operating connection between the actuator and the lever is normallyaccomplished by the spring, and the connection is transferred to the pinand slot when the tension in the spring is overcome by the force of thepush-button necessary to move a control member by its associatedactuating unit.

A pivoted latch is provided to act on each operated actuator and holdthe same in an operated or tuning position. As a result of the springconnection between an actuator and its associated 3O lever, there issufiicient cushion between them,

and hence sufficient cushion in the actuating unit as a whole to absorbany severe shock or jar applied to the control members to move them tothus prevent any damage in the complete tuning mechanism. At the sametime the operated position of a, control member is retained as soon asthe movement is absorbed. The cushioning for the control apparatus whenin operated position, results from the fact that the pin on the lever isspaced slightly, or is out of direct engagement the rotary control shaftand the resonant frequency changing means toaccurately and eflicientlytransmit motion from one to the other.

Referring now to the drawings, the control or tuner apparatus includes aframe having a pair of side plates l0 and II which may desirably bepreassembled and secured together as a unit by means of a plurality oftie-bars l2. A variable condenser I3 is rigidly mounted at the top ofthe frame for electrical connection with a radio reeeiver to tune thereceiver in the usual manner.

It is understood that I may employ resonant frequency changing meansother than a variable condenser.

The condenser I3 is adjusted to predetermined tuning positions by meansof control apparatus therefor, which includes a rotary shaft assembly i4rotatably supported in the frame plates l and ii and carrying thereon aplurality of cams or control members |6 which may also be designatedmore broadly as control means. The cams are supported on the shaft l ofthe rotary assembly l4 and normally held against rotation by means offriction washers I! and associated spacing collars |8. The friction isvaried by a unit including a cap-screw l9 and a knob 2| acting with theshaft i5 to move the control members and associated washers and collarsaxially relative to the shaft until all of these elements are heldtightly together against a rigid stop 22 on the rotary shaft. Thisstructure and operation i all fully described and claimed in Patent No.2,130,153, issued September 13, 1938. When the friction is removed fromthe control members l6 they may be adjusted to angular positions withreference to the rotary shaft, which correspond to predetermined tuningpositions for the condenser l3, and after the friction is applied to thecontrol members and they are frictionally retained in the adjustedangular positions, the condenser is automatically adjusted to a positioncorresponding to that of a selected control member when such controlmember is rotated by actuating mechanism as will be described.

The actuating mechanism for the rotary assembly l4 including the controlmembers IS includes a plurality of actuator units corresponding innumber to the control members It and all adapted to be selectivelyoperated from an accessible outside position on a radio receiver orother apparatus to which the control unit is applied. Each actuatorunit, includes a lever 23 pivotally supported upon a stationary shaft orframe member 24 secured in the frame plates Ill and II. Each lever 23 ispivotally supported at one end, and at the other end includes anengaging portion in the form of a roller 26 or the like for operatingengagement with a corresponding cam or control member l6, as shown inFigs. 1 and 2. Each lever 23 is pivoted by a corresponding actuator orselector member 21 slidably supported at one end by a frame plate 28,which in turn is supported on frame members 29 rigidly secured to theframe plates I0 and H of the frame for the control unit. Each actuator21 is connected to its corresponding lever by means of a guide pin 3| onthe lever riding in a correspond ing guide slot 32 in the actuator.Relative movement between the lever 23 and the actuator 21 is permittedby virtue of the length of the slot 32 and this relative movement islimited by the ends or shoulders 33 and 33' at the front and back endsrespectively of the slot.

As is evident from the above description and a consideration of thedrawings, a rather harsh, metallic feel could be evident at thepush-button 34 on the actuator when the engaging portion 26 of a leveris brought into contact with a corresponding control member l6 to movethe latter to an adjusted position. This is generally true of themanually operated automatic tuners of the prior art for radio receivers.I have overcome this difficulty and substituted a cushioned, pleasantfeel at the push-button 34 by including a spring in the connectionbetween the lever and its associated actuator. This general structure haadditional advantages as will be hereinafter more fully described. As tothe spring connection itself, however, this includes a coiled spring 36,which in the illustrated embodiment of the invention is of thecompression type. The spring 38 is supported upon the end of theactuator and rests at one end against a washer 31 which in turn isretained against longitudinal movement in one direction with referenceto the actuator 21 by means of shoulders 38 on such actuator. The otherend of the spring rests against a similar washer 39 which in turn bearsagainst a rounded portion 4| on the lever. The compression in the spring36 is suflicient to normally press the actuator 21 to a retractedposition with reference to the lever 23 with the pin 3| at the end 33'of the guide slot 32 (shown in full lines in Fig. 1). Although there isa connection between the lever and actuator through the pin andcorresponding guide slot, the effective operating connection in alongitudinal direction for some portion of the operating stroke inormally made through the spring 36.

In order to retain a selected control member I in its adjusted positionwith a roller 26 in a corresponding stopping cavity 25, such as shown inthe partially-dotted-line control member IS in Fig. 1, a pivoted latch42 is employed to releasalbly retain the selected actuator 21. The latch42 is pivotally supported in the frame members 29, is common to all ofthe actuator units. and is maintained under tension by the spring 43.shown in Fig. 1. Each actuator 21 is provided with a combinationlatching and stop shoulder 44 positioned at one end oi a cam-likeprojection 46 which acts to raise the latch 42 as an actuator is Pushedinwardly to operated position. When an actuator is in idle position theshoulder 44 engages the back of the frame plate 23 to limit the outwardmovement of the actuator and its associated lever. The spring 45 betweeneach lever 2-3, and a tie bar member l2 acts to pull an entire actuatingunit to idle position.

To operate the variable condenser l3 a selected push button 34 is pushedinwardly. Its associated actuating structure including an actuator orselector member 21 moves through a substantially longitudinal path, andwith the shoulders 38 pressing against the washer 31 for the spring 36,the latter exerts a force against the washer 39 and an engaging portion4| on the lever'to move the latter into engagement with a correspondingcontrol member ID. Until the operating force on the button 34 issufllcient to overcome the compression forces in the spring 33, theoperating force is applied to the lever through the spring, providing ayielding, cushioned feel at the button. As the operating force overcomesthe force of the spring, the shoulder 33 in the guide slot 32 engagesthe pin 3| (Fig. 3) and the lever and control member are pushed into setposition such as shown in dotted lines in Fig. 1. The spring 36 beingunder compression may act on the lever and assist in accomplishing thefinal movement of the control member to bring the roller 26 into thestopping cavity in the control member or cam IS.

The position of the shoulder 44 on the actuator is such with referenceto the operating stroke as a whole that it is pressed inwardly beyondthe latching edge of the latch 42, as shown in Fig. 3,

when the lever and control member are originally pressed into a setposition. The compression of spring 36, when the operator releases hisfinger from the button 34, urges the actuator and lever anaeoc inopposite directions and acts to retain the lever and control member inset position and at the same time press the latching shoulder 44 againstthe edge of the latch 42. The actuator and lever are spread apart sothat the pin 3! is out of direct engagement with its adjacent shoulder33 in the guide slot as shown in dotted lines in Fig. 1. with theactuator 2'! latched in this position. the connection between the lever23 and actuator in a substantially longitudinal direction is, so far asholding eflectiveness is concerned, through the spring at which is undercompression. In case of a shock, a jar, or actual manipulation of thecondenser it or rotary control assembly M, the linear space between theshoulders Stand 33 and pin 8! will take up the movement of any of thisstructure and it will be absorbed in the spring 36- without injury toany of such structure or parts thereof. At the same time, however, theactuator remains stationary and latched and the force of the springacting on the lever returns the control member to the dotted line setposition.

.The spring 36 is also important in the resetting operation for thecontrol member I6. Resetting is accomplished by loosening the screw itand-releasing some of pressure on the control member ll so that relativemovement between the members and the shaft 15 is possible. A selectedactuator unit is operatedto latched, set position, meanwhile, moving thecorresponding control member IE to a position as shown in dotted lines.Watching a dial scale (not shown) operatively invention in its preferredembodiment, it is connected to the shaft lli, such shaftis manually Irotated until it is at a position corresponding to a desired stationsetting. The spring in the meantime maintains a force on the heldcontrol'member, and urges the actuator against the latch. The frictionis applied to the control members after the resetting is entirelyaccomplished.

The rotary movement of the shaft I5 is transmitted to the resonantfrequency changing means or condenser l3 by structure including asupporting unit 48 mounted on the rotary shaft and keyed againstrotation thereon and a similar unit on the shaft for the condenser l3.Each unit includes a pair of radial arms 49 extending in differentangular directions from its associated shaft and is held thereon by ascrew 5|. A curved link 52 is pivotally connected to each pair ofcorresponding radial arms 49 on the two units 48 to provide a, sturdyconnection for accuratey and efficiently transmitting the movement ofthe rotary control shaft to the controlled resonant frequency changingmeans.

with an actuator 21 retained in latched position such as shown in theback in Fig. 1 and the third from the bottom in Fig. 2, the particularstation to which the receiver is tuned is readily discernible forindicating tabs can be supplied for each button. Upon pressing anotherbutton 34 inwardly the latch 42 is pivoted upwardly to release thepreviously latched actuator, and then pulled downwardly again by thespring 43 to latch the actuator being operated.

In the present invention, therefore, I provide a simple, inexpensive,yet efilcient control unit for a radio receiver which operates bylinearly movable push-buttons. The twopart actuating structure for thecontrol unit includes a yielding portion which provides a cushioned,pleasant feel" in operating a push-button, and permits. some amount ofplay in the actuating and control structure to absorb shocks, jars andthe like, while the control device is in an operated tuning understoodthat my invention is not limited thereby, but is limited only by thescope of the appended claims.

I claim:

l. A radio tuner including in combination a selector member, rotarycontrol means having an engageable edge, a pivoted lever operativelyconnected to said selector member and movable therewith, means includinga spring on the selector member applying a force to an edge a: saidlever intermediate the ends thereof for yieldably connecting said leverand selector member, with said lever engaging said control means on theedge thereof to directly move said control means to a predetermnied stopposition upon movement of the selector member.

2. In a radio tuner, the combination of rotatable control means, andmeans for rotating said control means, said means including a leveradapted to be moved about a pivot point and pivoting toward said controlmeans to engage and ,directly move the same, a selector member slidabletoward said control means to move said lever about its pivot point,means for supporting said selector member, and a yieldable member 3. Ina radio tuner having a frame and aa control member rotatably supportedthereon, the

combination of an actuator supported upon the frame for actuatingmovement thereon, a lever pivotally mountedvat one end upon said framehaving an engaging portion at the other end for engagement with therotary control member to directly move the same. and means operativelyconnecting said actuator with said pivoted lever intermediate the endsof the lever including spring means mounted at one end on said actuatorand applying a force at its other end to said lever intermediate theends of said lever to move said lever upon movement of said actuatorthrough at least a portion of the substantially linear travel thereof.

4. Control apparatus for a radio receiver including a substantiallylinearly movable actuator having an engaging shoulder intermediate theends thereof, a pivotally supported lever operatively connected withsaid actuator, and means for operatively connecting said actuator andsaid lever including a spring in operative connection at one end with acorresponding stop portion on said actuator, and in operative connectionwith said lever at the other end of the spring,

with said spring normally acting to drive said lever upon movement ofsaid actuator through a portion of its actuating stroke, and astopportion on said lever for engagement by said actuator shoulderduring the remaining portion ofthe actuating stroke of said actuator tomove said lever therewith. Y

5. In radio control apparatus having rotary control means, actuatingmeans for rotating the control means including a movable selector memberhaving an engaging shoulder intermediate the ends thereof, a secondselector member for operative connection with said rotary control.

7 means having an engaging portion thereon for engagement by saidengaging shoulder oi! the movable selector member, and means formaintaining said engaging portion and said am gaging shoulder out ofengagement during at least a portion of the operating stroke of themovable selector member.

6. In a radio tuner having a frame and a rotary control shaft mounted insaid frame, the combination of a plurality of actuating units'foroperative connection with said rotary shaft to rotate the same, each ofsaid actuating units including a pair of actuating members with one ofsaid members having a push-button on one end thereof and a latchingshoulder intermediate the ends thereof, with said other member having anengaging portion for operative connection with the rotaryshaft, meansoperatively connecting said two actuating members including acompression spring supported at one end of one member and operativelyconnected at the other end with the other member, a latch pivotallysupported upon said frame for latching engagement with the latchingshoulder on said one actuating member, with said latching shoulder beingpositioned on said one actuating member with reference to the length ofthe operating stroke of the actuating unit such that said shoulder ispressed beyond said latch in completing an operating stroke of theactuating unit and returned for latching engagement with said latchunder pressure of said compression spring, with one of said actuatingmembers being movable with respect to the other actuating "member whenthe latched actuating member is in latched position.

7. Tuning apparatus for a radio receiver including in combination arotary control member having a pair of substantially oppositely disposedcontrol portions each in a cam shape, alever pivotally mounted at one ofits ends independently of the axis for the rotary control member havinga part for originally engaging one cam-shaped control portion or theother of the control membar to move said control member to tuningposition, a slidable actuator operatively connected with said lever at apoint intermediate the pivoted end thereof and said engaging part, meansguidably supporting said actuator on said lever and means for mountingsaid actuator to support the same on an actuating stroke.

8. In radio tuning apparatus having frame means and movable frequencychanging means, the means for tuning said changing means including alever, an actuator supported adjacent one end on said frame means andsupported at its other end on said lever intermediate the ends of thelever, a spring on said actuator opera- 8 tively connected with saidlever to transmit operating force from said actuator to said lever, and

alatch on said frame means releasably engaging said actuatorintermediate the ends thereof.

9. In radio tuning apparatus having control means for determining achange in frequency, the means for operating the'control means includingin combination a lever-part mounted at one end portion and adapted forengaging the control means at its otherend portion, a longitudinallymovable actuator-part operatively connected with said lever-partintermediate said end portions, and a spring on said actuator-partapplying a force on said lever-part intermediate said end portionsduring at least a portion of the operating movement of theactuator-part.

10. In the tuning apparatus of claim 9, one of said two parts having anelongated guide aperture therein and the other part having a pin in saidaperture, said pin and the edge of said aperture acting to permit butlimit independent movement of one part relative to the other, and saidspring applying a force on each part during said independent movement.

11. In radio tuning apparatus having control means for determining achange in frequency, the means for operating the control means includingin combination a lever mounted at one end portion and adapted forengaging the control means at its other end portion, an actuatorsupported in said apparatus in a position extending longitudinally inthe apparatus and intermediate the two end portions of the lever andoperatively connected with said lever, and a spring acting on said leverand actuator at the operative connection thereof intermediate said twoend portions of the lever.

WILLIAM L. DUNN.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,070,538 Ross Aug. 19, 19131,948,473 Flaherty .1 Feb. 20, 1934 2,273,499 Teaf Feb. 17, 19422,275,369 Leishman Mar. 3, 1942 2,307,285 Mastney Jan. 5, 1943 FOREIGNPATENTS Number Country Date 94,131 I Sweden Jan. 13, 1939 510,186 GreatBritain July 28, 1939 Denmark Aug. 24, 1936

